This invention relates to telescopic spectacle assemblies and more particularly to a universally adjustable assembly for use with implanted intraocular lens assemblies.
As one can ascertain, the prior art is replete with many examples of intraocular lens assemblies. These lens assemblies are implanted in the eye of a patient and consist of an optic lens and haptic for fixation of the lens in a posterior or anterior chamber of the eye. Such implants have been devised in many different configurations and are useful for assisting visually handicapped persons.
For examples of such intraocular implants, reference is made to U.S. Pat. No. 4,681,585 entitled INTRAOCULAR IMPLANT issued on July 21, 1987 to R. Sayano et al. For further examples of such lenses reference is made to U.S. Pat. No. 4,681,586 issued on July 21, 1987 and entitled INTRAOCULAR LENS HAVING UNITARY INTEGRAL HAPTIC MEANS to R. L. Woods.
In any event, the intraocular lens has been extensively employed in regard to those patients which suffer from macular degeneration. Age related macular degeneration is the leading cause of visual loss in the United States of adults who are sixty years of age and older. Presently, it is estimated that over 150,000 people develop this disease each year. In regard to this particular disease there are two distinct types of macular degeneration which occur. A first type is known as atropic or 37 dry" type which results in a gradual atrophy of the sensory retina and pigment epithelium. A second type is referred to as the exudative or "wet" form. In this type new vessels proliferate from the choriocapillaris under the sensory retina which produce hemorrhaging and scarring This type of macular degeneration may be treated by laser photocoagulation providing that the neovascular tissue is outside the foveal avascular zone.
In any event, patients who have lost vision due to macular degeneration can be helped by optical aids such as high-plus lenses and telescopic assemblies that magnify an object to be viewed. The disadvantages are that high-plus lenses need to be held very close to the material or object and telescopic assemblies produce a very small visual field.
Hence the prior art attempted to improve the visual field of a telescope by using an intraocular lens as a high minus ocular. This procedure serves to enlarge the visual field three times greater than the external telescope. Unfortunately, using this system without spectacles makes the patient extremely myoptic and both central and peripheral vision can be lost. Hence there are new ocular lenses which have been developed which improve on such optical devices. In general such ocular lenses have a central portion which is either at a plus or a minus magnification and comprises a central zone in order to improve the patient's visual perception. In any event, all such devices are associated with spectacles which essentially form part of the telescopic assembly with the intraocular lens serving as the ocular lens component of the telescope and the spectacles or glasses serving as the objective lens. Hence in spite of the advances made in this particular field, there is still a need for an improved spectacle assembly to be worn by a person who has intraocular lenses implanted.
The design of such spectacle assemblies is difficult and, if not properly implemented, result in undesirable visual characteristics thus rendering it extremely difficult for the patient to see under various different circumstances. For examples of the problem and further examples of additional references as well as examples of improved intraocular lenses reference is made to a paper entitled 37 Optical Evaluation of Two New Intraocular Lenses for Age-Related Macular Degeneration" by J. Koziol et al. published by the Department of Opthalomogy, Eye and Ear Infirmary, University of Illinois, College of Medicine at Chicago. Reprint requests of this article can be obtained by writing to 1855 Taylor Street, Chicago, Ill. 60612 to Dr. Gholam A. Peyman. In any event, and as indicated, in spite of the above the most modern treatment requires the patient to wear a pair of spectacles which should be designed to accommodate the patient's particular visual problems. It is the design of the spectacles which enables the patient to obtain improved vision.
Hence as one can ascertain, such spectacles have to be designed with a consideration of many visual aspects required by a patient. The spectacles as designed must accommodate particular patient characteristics in order to enable proper vision in conjunction with an implanted intraocular lens assembly. Present systems do not deal with astigmatic (cylindrical) prescriptions and the use of present techniques do not accommodate for such astigmatism. Essentially, as one can ascertain, the persons who receive intraocular implants are defined as low-vision patients and their problems are unique.
The history has shown that dealing with the low-vision patient is much more complicated than one suspects in the beginning. In any event, alignment is critical to the patient's viewing success. One must take into consideration various aspects of the spectacle assembly which will enable a low-vision patient having an intraocular implant to view in a proper manner. Hence one must consider the pantascopic or retroscopic tilt which relates to the objective lens optical axis. A patient must be taught how to align the entire system as compared to mounting it on a pair of glasses. Other considerations such as binocularity are also extremely important.
In any event, one must also understand that after a lens is implanted and the patient's vision worsens then the telescopes that they employ will reach a condition where the patient will need more magnification than can be supplied with a single objective lens assembly. In this manner one cannot easily replace the spectacle assembly without major modifications. In any event, as one can ascertain from the above, the provision of a spectacle assembly for use with an implanted intraocular lens is an extremely important part of a total vision system.
It is therefore an objective of the present invention to provide an improved telescopic spectacle assembly for use with implanted intraocular lens assemblies.
It is a further objective of the present invention to provide a universally adjustable telescopic spectacle assembly for use with implanted intraocular lenses.